# cd /home/study                                                                                                                  
  2 # if log.txt -e ./bash
  3 # then
  4 #     echo "文件存在！"
  5 # else
  6 #     echo "文件不存在！"
  7 # fi
  8 
  9 cd /home/study
 10 if [ -e log.txt ]
 11 then
 12     echo '文件已存在!'
 13 else
 14     echo '文件不存在!'
 15 fi


